[The prognosis and related factors impacting renal response in newly diagnosed multiple myeloma patients with renal impairment].

Objective: To investigate the prognosis and related factors impacting renal response in newly diagnosed multiple myeloma (NDMM) patients with renal impairment. Methods: A total of 375 NDMM patients diagnosed at the Department of Hematology, the First Affiliated Hospital of Nanjing Medical University from August 2012 to April 2022 were retrospectively recruited. Patients were categorized into non-renal impairment group(n=273) and renal impairment group (n=102) according to renal function at initial diagnosis. All patients received≥2 cycles of bortezomib-based induction chemotherapy after admission. The hematological response included stringent complete response (sCR), complete response (CR), very good partial response (VGPR), partial response (PR) and stable disease (SD). The renal responses were defined as CR, PR, minor response (MR) and non-response (NR). General clinical data of the patients were collected, and patients were followed up by telephone. The follow-up deadline was December 3, 2022, and the median follow-up time [M (Q1, Q3)] was 42 (22, 61) months. Kaplan-Meier analysis was used to plot the survival curve. The log-rank test was utilized for inter-group comparisons. Multivariate logistic regression modeling facilitated the exploration of associated factors impacting renal response. Results: In the renal impairment group, there were 68 males and 34 females with a median age [M (Q1, Q3)] of 64 (58, 69) years. In the non-renal impairment group, there were 149 males and 124 females with a median age of 62 (54, 68) years. Compared with the renal impairment group, the age, lactate dehydrogenase and 24-hour urinary protein quantity were increased, the proportion of patients with light chain M protein and the proportion of patients at the DS-Ⅲ stage, ISS-Ⅲ stage and R-ISS-Ⅲ stage were higher, the hemoglobin level and the proportion of patients receiving autologous hematopoietic stem cell transplantation were lower in the renal impairment group (all P<0.05). In 102 patients with renal impairment, renal responses of CR, PR, MR and NR were obtained in 53 (52.0%), 8 (7.9%), 18 (17.6%), 23 (22.5%) patients, respectively, and the overall response rate was 77.5% (79/102). Kaplan-Meier survival curve revealed that the median progression-free survival (PFS) was 24.0 (95%CI: 18.3-29.7) months in the renal impairment group, which was shorter than 31.0 (95%CI: 24.7-37.3) months in the non-renal impairment group (P=0.003). The median overall survival (OS) was 46.0 (95%CI: 36.5-55.5) months in the renal impairment group, which was shorter than 79.0 (95%CI: 59.9-98.1) months in the non-renal impairment group (P=0.002). Among the renal impairment group, patients with renal response of less than PR exhibited a median PFS of 19.0 (95%CI: 9.7-28.3) months, which was shorter than 28.0 (95%CI: 21.4-34.5) months for those achieving PR or better (P=0.048). The median OS was 31.0 (95%CI: 23.5-38.5) months in renal response with less than PR group, which was also worse than 57.0 (95%CI: 42.8-71.2) months for those who achieved PR or better (P=0.003). The results of multivariate logistic regression showed that hematological response achieving VGPR or better was a factor associated with renal response achieving PR (OR=4.20, 95%CI: 1.20-14.68, P=0.025). Conclusions: The prognosis of NDMM patients with renal impairment is poor. The hematological response with VGPR or better is related to the renal response achieving PR.

Proteasome inhibition suppresses the induction of lipocalin-2 upon systemic lipopolysaccharide challenge in mice.

Lipocalin-2 (Lcn2), a protein secreted by immune-activated cells, including reactive astrocytes, is detrimental to the brain and induces neurodegeneration. We previously showed that Lcn2 levels are reduced in primary mouse astrocytes after treatment with the proteasome inhibitor bortezomib (BTZ). However, it remains unknown whether a decrease in Lcn2 levels after BTZ treatment can also be observed in vivo and whether it reduces neurotoxicity during lipopolysaccharide (LPS)-induced systemic inflammation in vivo. To answer these questions, we performed LPS challenge experiments by intraperitoneal injection in mice and found that Lcn2 levels were significantly increased in the brain, recapitulating in vitro experiments using astrocytes. Co-administration of LPS and BTZ reduced the Lcn2 levels compared to the levels in LPS-treated controls. Upon LPS challenge, the expression levels of glial marker genes were upregulated in the mouse brain. Of note, this upregulation was hampered by the co-administration of BTZ. Taken together, our results suggested that BTZ can reduce LPS-induced Lcn2 levels and may alleviate LPS-induced neuroinflammation and neurotoxicity in mice.

Integrating protein interaction and pathway crosstalk network reveals a promising therapeutic approach for psoriasis through apoptosis induction.

Psoriasis is a complex inflammatory skin disease manifested by altered proliferation and differentiation of keratinocytes with dysfunctional apoptosis. This study aimed to identify regulatory factors and comprehend the underlying mechanisms of inefficient apoptosis to open up promising therapeutic approaches. Incorporating human protein interactions, apoptosis proteins, and physical relationships of psoriasis-apoptosis proteins helped us to generate a psoriasis-apoptosis interaction (SAI) network. Subsequently, topological and functional analyses of the SAI network revealed effective proteins, functional modules, hub motifs, dysregulated pathways and transcriptional gene regulatory factors. Network pharmacology, molecular docking and molecular dynamics simulation methods identified the potential drug-target interactions. RELA, MAPK1, MAPK3, MMP9, IL1B, AKT1 and STAT1 were revealed as effective proteins. The MAPK1-MAPK3-RELA motif was identified as a hub regulator in the crosstalk between 41 pathways. Among all pathways, "lipid and atherosclerosis" was found to be the predominant pathway. Acetylcysteine, arsenic-trioxide, ß-elemene, bortezomib and curcumin were identified as potential drugs to inhibit pathway crosstalk. Experimental verifications were performed using the literature search, GSE13355 and GSE14905 microarray datasets. Drug-protein-pathway interactions associated with apoptosis were deciphered. These findings highlight the role of hub motif-mediated pathway-pathway crosstalk associated with apoptosis in the complexity of psoriasis and suggest crosstalk inhibition as an effective therapeutic approach.

Antibody-Mediated Rejection in Liver Transplantation: Immuno-Pathological Characteristics and Long-Term Follow-Up.

The diagnosis of liver antibody-mediated rejection (AMR) is challenging and likely under-recognized. The association of AMR with donor-specific antibodies (DSA), and its clinical course in relation to pathologic findings and treatment are ill defined. We identified cases of liver AMR by following the criteria outlined by the 2016 Banff Working Group. Patient demographics, native liver disease, histopathologic findings, treatment type, clinical outcome, and transaminase levels during AMR diagnosis, treatment, and resolution were determined. Patients (n = 8) with AMR average age was 55.2 years (range: 19-68). Seven of eight cases met the Banff criteria for AMR. Personalized treatment regimens consisted of optimization of immunosuppression, intravenous pulse steroids, plasmapheresis, IVIG, rituximab, and bortezomib. Five patients experienced complete resolution of AMR, return of transaminases to baseline, and decreased DSA at long-term follow-up. One patient developed chronic AMR and two patients required re-transplantation. Follow-up after AMR diagnosis ranged from one to 11 years. Because AMR can present at any time, crossmatch, early biopsy, and routine monitoring of DSA levels should be implemented following transaminase elevation to recognize AMR. Furthermore, treatment should be immediately implemented to reverse AMR and prevent graft failure, chronic damage, re-transplantation, and possibly mortality.

Bortezomib, lenalidomide, and dexamethasone versus bortezomib, doxorubicin, and dexamethasone in newly diagnosed multiple myeloma.

Bortezomib, lenalidomide, and dexamethasone (VRD), and bortezomib, doxorubicin, and dexamethasone (PAD), are commonly used in induction regimens for patients with newly diagnosed multiple myeloma (NDMM) in China. This real-world study enrolled 390 patients, 195 receiving VRD and 195 receiving PAD induction. The primary endpoint was progression-free survival (PFS) and stringent complete remission/complete remission. Across the entire cohort, VRD demonstrated significantly improved five-year overall survival (OS) (74% vs. 59%, p = 0.0024) and five-year PFS (67% vs. 37%, p = 0.0018) compared to PAD. Notably, the median OS and PFS were not reached for VRD-treated patients, while they were 77 months (60-not reached [NR]) and 46 months (36-NR), respectively, for PAD. In patients with standard-risk cytogenetics, VRD showed superior five-year OS (83% vs. 58%, p = 0.0038) and PFS (78% vs. 48%, p = 0.0091) compared to PAD. However, these differences were not statistically significant in high-risk patients. For transplanted patients, VRD was associated with superior five-year OS (91% vs. 67%, p = 0.014) and PFS (79% vs. 47%, p = 0.015) compared to PAD. In non-transplanted patients, VRD showed a trend towards improved five-year OS (p = 0.085) and PFS (p = 0.073) compared to the PAD group. In conclusion, VRD displayed superior OS and PFS outcomes in standard-risk patients and those who underwent transplantation. These findings suggest potential advantages of VRD over PAD in real-world clinical settings for NDMM treatment. However, due to the imbalance in transplantation rates between the VRD and PAD groups, limitations in testing for high-risk cytogenetic abnormalities (HRA), and the difference between the received cycles and salvage therapies, the conclusions of this study should be interpreted with caution.

Quadruplet therapy for newly diagnosed myeloma: comparative analysis of sequential cohorts with triplet therapy lenalidomide, bortezomib and dexamethasone (RVd) versus daratumamab with RVD (DRVd) in transplant-eligible patients.

Lenalidomide, bortezomib, and dexamethasone (RVd) have previously been established as standard-of-care induction therapy for newly diagnosed multiple myeloma (NDMM). More recently, randomized phase 3 data have demonstrated the benefit of the addition of daratumumab (Dara-RVd) to the RVd backbone in terms of improved both depth of response and long-term survival benefit as measured by progression-free survival (PFS). Our group has previously published on a historical cohort of 1000 NDMM patients uniformly treated with RVd induction with impressive both PFS and overall survival. Here, we present a comparative analysis of our RVd cohort with a recent cohort of 326 patients induced with Dara-RVd at our institution with intent to transplant. This analysis demonstrates the utility of this regimen in real-world clinical practice and provides additional insights into D-RVd performance in patient subsets often underrepresented in clinical trials, as well as the impact of daratumumab in maintenance for NDMM patients.

Proteasome inhibition enhances the anti-leukemic efficacy of chimeric antigen receptor (CAR) expressing NK cells against acute myeloid leukemia.

BACKGROUND: Relapsed and refractory acute myeloid leukemia (AML) carries a dismal prognosis. CAR T cells have shown limited efficacy in AML, partially due to dysfunctional autologous T cells and the extended time for generation of patient specific CAR T cells. Allogeneic NK cell therapy is a promising alternative, but strategies to enhance efficacy and persistence may be necessary. Proteasome inhibitors (PI) induce changes in the surface proteome which may render malignant cells more vulnerable to NK mediated cytotoxicity. Here, we investigated the potential benefit of combining PIs with CAR-expressing allogeneic NK cells against AML. METHODS: We established the IC50 concentrations for Bortezomib and Carfilzomib against several AML cell lines. Surface expression of class-I HLA molecules and stress-associated proteins upon treatment with proteasome inhibitors was determined by multiparameter flow cytometry. Using functional in vitro assays, we explored the therapeutic synergy between pre-treatment with PIs and the anti-leukemic efficacy of NK cells with or without expression of AML-specific CAR constructs against AML cell lines and primary patient samples. Also, we investigated the tolerability and efficacy of a single PI application strategy followed by (CAR-) NK cell infusion in two different murine xenograft models of AML. RESULTS: AML cell lines and primary AML patient samples were susceptible to Bortezomib and Carfilzomib mediated cytotoxicity. Conditioned resistance to Azacitidine/Venetoclax did not confer primary resistance to PIs. Treating AML cells with PIs reduced the surface expression of class-I HLA molecules on AML cells in a time-and-dose dependent manner. Stress-associated proteins were upregulated on the transcriptional level and on the cell surface. NK cell mediated killing of AML cells was enhanced in a synergistic manner. PI pre-treatment increased effector-target cell conjugate formation and Interferon-γ secretion, resulting in enhanced NK cell activity against AML cell lines and primary samples in vitro. Expression of CD33- and CD70-specific CARs further improved the antileukemic efficacy. In vivo, Bortezomib pre-treatment followed by CAR-NK cell infusion reduced AML growth, leading to prolonged overall survival. CONCLUSIONS: PIs enhance the anti-leukemic efficacy of CAR-expressing allogeneic NK cells against AML in vitro and in vivo, warranting further exploration of this combinatorial treatment within early phase clinical trials.

A case of heavy-chain deposition disease with good long-term renal survival and a literature review.

BACKGROUND: Monoclonal immunoglobulin deposition disease (MIDD) is characterized by the deposition of nonamyloid monoclonal immunoglobulin and its free fragment light chain and/or heavy chain in systemic tissues and organs, and the kidney is most vulnerable organs. MIDD can be divided into three types: light-chain deposition disease (LCDD), light and heavy chain deposition disease (LHCDD), and heavy-chain deposition disease (HCDD), of which LHCDD and HCDD are rarer (Bridoux et al. in Kidney Int 2015;87:698-711; Preud'homme et al. in Kidney Int 1994;46:965-72). Poor outcome in most HCDD, but in this paper, we will report a case of HCDD with good long-term renal survival and review the literature for reference. CASE PRESENTATION: A 32-year-old man presented to our department with skin laxity and nephritic syndrome, accompanied by an significant increase of serum creatinine and received short-term hemodialysis treatment. Both the blood and urine free light chain ratio increased significantly. Renal biopsy showed mesangial nodular glomerulosclerosis on light microscopy, and immunofluorescence staining showed positivity for γ-heavy chain (HC), with negative light chain (LC) staining; the diagnosis was considered HCDD. After six courses of bortezomib combined with dexamethasone chemotherapy and thalidomide 100 mg/day, the renal function gradually recovered, while also with proteinuria and hematuria significantly improved. The blood and urine free light chain ratio decreased to normal. Until now, the patient has been followed for four years, and long-term renal survival has been observed. CONCLUSION: Herein, we report a case presenting with proteinuria, hematuria, renal impairment, and skin laxity, and a renal biopsy showed linear IgG deposition in the glomerular basement membranes and tubular basement membrane. However, they ultimately proved to have HCDD. Bortezomib combined with dexamethasone, and oral thalidomide led to a good long-term renal survival. We also provide a review of currently available literature, and this is the first large-scale review summarizing the characteristics of HCDD up to date.

Real-world treatment trends and triple class exposed status in newly diagnosed multiple myeloma patients in Japan: A retrospective claims database study.

Treatment trends for newly diagnosed multiple myeloma (NDMM) are not fully evaluated in real-world settings in the Japanese population. Triple-class exposed (TCE) patients with relapsed or refractory MM have a poor prognosis and limited treatment options. To clarify characteristics, treatment trends, and TCE status in Japanese patients with MM, we conducted a retrospective, non-interventional study. Data from patients with MM were extracted from a Japanese claims database between 2015 and 2022: this study identified patients with NDMM prescribed daratumumab (D), lenalidomide (R), and/or bortezomib (V) as 1st-line treatment. The patient characteristics and treatment trends were analyzed for non-transplant and transplant groups. Of 1,784 patients, non-transplant patients (n = 1,656, median age 75 years [range: 37-94]) received R+dexamethasone (Rd) (24.7%), Vd (23.8%), and RVd (15.6%) and transplant patients (n = 128, median age 61 years [range: 35-73]) received RVd (49.5%), Vd (18.7%), and DVd (8.4%) in 1st line. In the non-transplant group, the commonly prescribed treatment regimens were Rd for patients aged ≥75 years, Vd for patients aged 65-74 years, and RVd for patients aged <65 years. Patients with renal or cardiac dysfunction commonly received Vd or Rd, respectively. In the transplant group, 107 (83.6%) and 20 (15.6%) patients received transplantation in the 1st and 2nd lines, respectively. The top three regimens as induction therapy before stem cell transplantation were RVd (49.5%), Vd (18.7%), or DVd (8.4%) in 1st line. Cumulative TCE patients by 5th line were 351 (21.2%) and 56 (43.8%) for non-transplant and transplant patients, respectively. TCE ratio at each line gradually increased from 1st to 5th line (11.1-69.2% in the non-transplant group and 21.1-100% in the transplant group, respectively). Of 184 TCE patients in the non-transplant group, 89.7% received sequencing treatments including DRd, RVd, and DVd, and 10.3% received D-RVd in 1st line.

Doxycycline Plus Bortezomib-Containing Regimens for the Treatment of Light-Chain Amyloidosis in the Frontline Setting: Experience from the Amyloidosis Program of Calgary.

Background: Pre-clinical and retrospective data suggest that doxycycline added to treatment regimens has benefit in AL amyloidosis. However, a recent multicenter, open-label, randomized controlled trial in AL amyloidosis patients treated with CyBorD did not demonstrate a progression-free survival (PFS) or cardiac PFS benefit with added doxycycline. Objective: The main objective of this study was to explore the role of doxycycline combined with bortezomib-containing regimens (BCRs) for newly diagnosed AL amyloidosis patients with cardiac involvement and to compare them with a cohort of concurrent patients treated with BCR only. Material and Methods: AL amyloidosis patients, newly diagnosed between January 2012 and March 2022, who were treated with BCR at the Amyloidosis Program of Calgary (APC) were evaluated. Results: Sixty-four concurrent patients were identified. Thirty-nine patients received doxycycline in addition to BCR (BCR-D) for a median of 8 months. The overall response rate was similar among the groups. No significant differences in VGPR/CR, dFLC at 1 month, time to first response, time to best response, or organ responses were noted between the BCR alone and BCR-D groups. Summary and Conclusions: Our retrospective study demonstrated that doxycycline combined with BCR failed to prolong OS, PFS, or cardiac responses compared with BCR alone in patients with cardiac AL amyloidosis.

Bortezomib-induced neuropathy in multiple myeloma manifesting as foot drop due to peroneal nerve palsy.

We present the case of a man in his 50s with multiple myeloma who developed foot drop after receiving bortezomib-dexamethasone combination chemotherapy. Diagnostic evaluations, including haematological parameters, nerve conduction studies and imaging, were performed to confirm the diagnosis and assess the extent of neuropathy. He was managed conservatively with analgesics and vitamin supplements, and bortezomib was temporarily withheld. The neuropathy gradually improved, and bortezomib was successfully reintroduced without recurrence of foot drop. Bortezomib-induced foot drop is a rare complication of bortezomib-based therapy in patients with multiple myeloma. Early recognition and intervention are crucial to minimise impact on quality of life. This case report emphasises the safe reintroduction of bortezomib post-neuropathy resolution, emphasising the importance of early recognition and multidisciplinary management.

Cost-per-responder analysis of patients with lenalidomide-refractory multiple myeloma receiving ciltacabtagene autoleucel in CARTITUDE-4.

Introduction: Ciltacabtagene autoleucel (cilta-cel) is a chimeric antigen receptor T-cell therapy approved for patients with relapsed/refractory multiple myeloma (RRMM). In the phase 3 trial, CARTITUDE-4 (NCT04181827), cilta-cel demonstrated improved efficacy vs. standard of care (SOC; daratumumab plus pomalidomide and dexamethasone [DPd] or pomalidomide plus bortezomib and dexamethasone [PVd]) with a ≥ complete response (≥CR) rate of 73.1% vs. 21.8%. Methods: A cost-per-responder model was developed to assess the value of cilta-cel and SOC (87% DPd and 13% PVd) based on the CARTITUDE-4 trial data from a US mixed payer perspective (76.7% commercial, 23.3% Medicare). The model was developed using progression-free survival (PFS), overall survival (OS), and ≥CR endpoints from CARTITUDE-4 over a period of 25.4 months. Inpatient stays, outpatient visits, drug acquisition, administration, and monitoring costs were included. The base-case model assumed an inpatient setting for each cilta-cel infusion; another scenario included 30% outpatient and 70% inpatient infusions. Costs of managing grade 3-4 adverse events (AEs) and grade 1-4 cytokine release syndrome and neurotoxicity were included. Subsequent therapy costs were incurred after disease progression; terminal care costs were considered upon death events. Outcomes included total cost per treated patient, total cost per complete responder, and cost per month in PFS between cilta-cel and SOC. Costs were adjusted to 2024 US dollars. Results: Total cost per treated patient, total cost per complete responder, and total cost per month in PFS were estimated at $704,641, $963,941, and $30,978 for cilta-cel, respectively, and $840,730, $3,856,559, and $42,520 for SOC over the 25.4-month period. Cost drivers included treatment acquisition costs before progression and subsequent treatment costs ($451,318 and $111,637 for cilta-cel; $529,795 and $265,167 for SOC). A scenario analysis in which 30% of patients received an outpatient infusion (assuming the same payer mix) showed a lower cost per complete responder for cilta-cel ($956,523) than those with an infusion in the inpatient setting exclusively. Discussion: This analysis estimated that cost per treated patient, cost per complete responder, and cost per month in PFS for cilta-cel were remarkably lower than for DPd or PVd, highlighting the substantial clinical and economic benefit of cilta-cel for patients with RRMM.

Circular RNA_0003489 reflects unfavorable treatment response and shortened survival in newly diagnosed multiple myeloma patients who receive bortezomib-based induction therapy.

OBJECTIVES: Circular RNA_0003489 (Circ_0003489) promotes multiple myeloma (MM) progression and bortezomib resistance in MM cells, while its potential as a biomarker in newly diagnosed MM (NDMM) patients is unclear. Thus, this study aimed to investigate the association of circ_0003489 expression with treatment response and survival in NDMM patients who received bortezomib-based induction therapy. METHODS: Bone marrow (BM) specimens from 85 NDMM patients at diagnosis or before treatment and from 15 donor controls during BM examination were retrieved in this retrospective study. Circ_0003489 derived from BM plasma cells was detected by reverse transcription-quantitative polymerase chain reaction and cut by quartile and median for further analysis. RESULTS: Circ_0003489 expression was increased in NDMM patients versus donor controls (P < 0.001). Circ_0003489 quartile was positively correlated with BM plasma cells (P = 0.040), international staging system (ISS) stage (P = 0.007), the revision of ISS stage (P = 0.003), beta-2-microglobulin (P = 0.011), and lactate dehydrogenase (P = 0.042) in NDMM patients. Increased circ_0003489 quartile was linked with a lower possibility of achieving complete response (P = 0.020) and partial response or better (P = 0.041) in NDMM patients. Elevated circ_0003489 expression cut by quartile (P = 0.020) and cut by median (P = 0.006) were linked with decreased progression-free survival (PFS) in NDMM patients. Increased circ_0003489 expression cut by median was associated with shortened overall survival (OS) in NDMM patients (P = 0.038). Meanwhile, higher circ_0003489 quartile independently forecasted poorer PFS (hazard ratio = 1.342, P = 0.045), but not OS in NDMM patients. CONCLUSION: Circ_0003489 expression is increased and reflects unfavorable treatment response and survival in NDMM patients who receive bortezomib-based induction therapy.

Combination of bortezomib and venetoclax targets the pro-survival function of LMP-1 and EBNA-3C of Epstein-Barr virus in spontaneous lymphoblastoid cell lines.

Epstein-Barr virus (EBV) manipulates the ubiquitin-proteasome system and regulators of Bcl-2 family to enable the persistence of the virus and survival of the host cells through the expression of viral proteins in distinct latency patterns. We postulate that the combination of bortezomib (proteasome inhibitor) and venetoclax (Bcl-2 inhibitor) [bort/venetoclax] will cause synergistic killing of post-transplant lymphoproliferative disorder (PTLD) through targeting the pro-survival function of latent viral proteins such as latent membrane protein-1 (LMP-1) and EBV nuclear antigen-3C (EBNA-3C). Bort/venetoclax could synergistically kill spontaneous lymphoblastoid cell lines (sLCLs) derived from patients with PTLD and EBV-associated hemophagocytic lymphohistiocytosis by inducing DNA damage response, apoptosis and G1-S cell cycle arrest in a ROS-dependent manner. Bortezomib potently induced the expression of Noxa, a pro-apoptotic initiator and when combined with venetoclax, inhibited Mcl-1 and Bcl-2 simultaneously. Bortezomib prevented LMP-1 induced proteasomal degradation of IκBα leading to the suppression of the NF-κB signaling pathway. Bortezomib also rescued Bcl-6 from EBNA-3C mediated proteasomal degradation thus maintaining the repression of cyclin D1 and Bcl-2 causing G1-S arrest and apoptosis. Concurrently, venetoclax inhibited Bcl-2 upregulated by either LMP-1 or EBNA-3C. Bort/venetoclax decreased the expression of phosphorylated p65 and Bcl-2 at serine 70 thereby suppressing the NF-κB signaling pathway and promoting apoptosis, respectively. These data corroborated the marked suppression of the growth of xenograft of sLCL in SCID mice (p<0.001). Taken together, the combination of bortezomib and venetoclax targets the pro-survival function of LMP-1 and EBNA-3C of Epstein-Barr virus in spontaneous lymphoblastoid cell lines.

Efficacy of CARVYKTI in CARTITUDE-4 versus other conventional treatment regimens for lenalidomide-refractory multiple myeloma using inverse probability of treatment weighting.

Aim: The phase III randomized controlled trial (RCT) CARTITUDE-4 (NCT04181827) demonstrated superiority of CARVYKTI (ciltacabtagene autoleucel; cilta-cel) over daratumumab, pomalidomide and dexamethasone (DPd) and pomalidomide, bortezomib and dexamethasone (PVd) for relapsed/refractory multiple myeloma (RRMM) patients who have received one to three prior line(s) of therapy (LOT[s]) including an immunomodulatory agent and a proteasome inhibitor, and are refractory to lenalidomide. These analyses estimate the relative efficacy between cilta-cel and other common treatment regimens, for which no direct comparative evidence is available. Materials & methods: Patient data were available from the CARTITUDE-4, CASTOR, CANDOR and APOLLO RCTs. Imbalances between cohorts on key patient characteristics were adjusted for using inverse probability of treatment weighting (IPTW). Relative efficacies were estimated with response rate ratios (RRs) and 95% confidence intervals (CIs) for overall response rate (ORR), very good partial response or better rate (≥VGPR) and complete response or better rate (≥CR), and with hazard ratios (HRs) and 95% CIs for progression-free survival (PFS). Sensitivity analyses using different analytical methods and additional covariates were explored. Results: Key characteristics were well balanced across cohorts after IPTW. Cilta-cel showed statistically significant benefit in PFS (HRs: 0.11-0.51), ≥VGPR (RRs: 1.51-5.13) and ≥CR (RRs: 2.90-35.24) versus all comparators, and statistically significant improvements in ORR over most comparator regimens (RRs: 1.22-1.90). Results were consistent across sensitivity analyses. Conclusion: Cilta-cel demonstrated benefit over other common treatment regimens, highlighting its potential to become a new standard of care option for lenalidomide-refractory RRMM patients with one to three prior LOT(s). These comparisons help to demonstrate the improved efficacy of cilta-cel in countries where the standard of care may differ from DPd/PVd.

Dihydrolipoamide dehydrogenase (DLD) is a novel molecular target of bortezomib.

Proteasome inhibitors (PIs), such as bortezomib and calfizomib, were backbone agents in the treatment of multiple myeloma (MM). In this study, we investigated bortezomib interactors in MM cells and identified dihydrolipoamide dehydrogenase (DLD) as a molecular target of bortezomib. DLD catalyzes the oxidation of dihydrolipoamide to form lipoamide, a reaction that also generates NADH. Our data showed that bortezomib bound to DLD and inhibited DLD's enzymatic function in MM cells. DLD knocked down MM cells (DLD-KD) had decreased levels of NADH. Reduced NADH suppressed assembly of proteasome complex in cells. As a result, DLD-KD MM cells had decreased basal-level proteasome activity and were more sensitive to bortezomib. Since PIs were used in many anti-MM regimens in clinics, we found that high expression of DLD correlated with inferior prognosis of MM. Considering the regulatory role of DLD in proteasome assembly, we evaluated DLD targeting therapy in MM cells. DLD inhibitor CPI-613 showed a synergistic anti-MM effect with bortezomib in vitro and in vivo. Overall, our findings elucidated DLD as an alternative molecular target of bortezomib in MM. DLD-targeting might increase MM sensitivity to PIs.

Super enhancer acquisition drives expression of oncogenic PPP1R15B that regulates protein homeostasis in multiple myeloma.

Multiple myeloma is a hematological malignancy arising from immunoglobulin-secreting plasma cells. It remains poorly understood how chromatin rewiring of regulatory elements contributes to tumorigenesis and therapy resistance in myeloma. Here we generate a high-resolution contact map of myeloma-associated super-enhancers by integrating H3K27ac ChIP-seq and HiChIP from myeloma cell lines, patient-derived myeloma cells and normal plasma cells. Our comprehensive transcriptomic and phenomic analyses prioritize candidate genes with biological and clinical implications in myeloma. We show that myeloma cells frequently acquire SE that transcriptionally activate an oncogene PPP1R15B, which encodes a regulatory subunit of the holophosphatase complex that dephosphorylates translation initiation factor eIF2α. Epigenetic silencing or knockdown of PPP1R15B activates pro-apoptotic eIF2α-ATF4-CHOP pathway, while inhibiting protein synthesis and immunoglobulin production. Pharmacological inhibition of PPP1R15B using Raphin1 potentiates the anti-myeloma effect of bortezomib. Our study reveals that myeloma cells are vulnerable to perturbation of PPP1R15B-dependent protein homeostasis, highlighting a promising therapeutic strategy.